Problem: A rectangle is $4$ units long. The rectangle is also $2$ units wide. What is its perimeter?
Solution: $4\text{ }$ $2\text{ }$ The perimeter is the total length of all the sides of the shape added together. Add up the lengths of the sides: $ \text{perimeter} = {2} + {4} + {2} + {4} $ $ \text{perimeter} = 12\text{ } $